Unloading of grain from harvesters such as combines, is typically accomplished using an elongate unloading conveyor. Such unloading conveyors typically are helical auger type conveyors contained in a tubular housing. The conveyors have a free or discharge end portion including a discharge opening through which the grain is propelled by the operation of the conveyor. On some conveyors, the discharge opening faces longitudinally or endwardly such that the grain is propelled more longitudinally outwardly, and on others the opening faces more downwardly such that the grain is correspondingly propelled more downwardly.
For many years, unloading conveyors have included rubbery boots configured for guiding or directing the grain discharged therefrom. However, such boots are not typically adjustable, and provide only minimal grain flow control and guidance, and little or no extension of the effective length of the conveyor. Such boots also do not provide a closure capability to prevent entry of contaminants, nor an ability to prevent dribbling of grain after use.
Rigid spouts for the discharge openings of unloading conveyors are also known, some of which being adjustable. Reference in this regard, Huen U.S. Pat. No. 2,625,001, entitled Grain Unloading Attachment, issued Jan. 13, 1953. This spout provides an extension ability, and some degree of remotely adjustable grain flow for an endwardly facing discharge opening, but provides no closure capability whatsoever, nor does it prevent grain dribbling. And, if move to an upwardly extending position so as to provide some closure, the spout would serve as a funnel for directing contaminants, rain and the like, into the end of the conveyor.
Haag U.S. Pat. No. 5,167,581, entitled Directable Spout For A Conveyor, issued Dec. 1, 1992, discloses a spout for a downwardly facing discharge opening, for directing grain directly down through a trapezoidal funnel incorporating a deflection plate to change the angle of discharge. However, no closure nor dribble prevention is provided, and the directional control capability is limited essentially to the region directly below the funnel, and no substantial effective length extension is achievable.
In regard to the importance of control or adjustment of grain flow, often, when unloading grain into a grain truck or wagon, the harvester and truck or wagon will be initially relatively positioned such that the receiving container is desirable positioned beneath the discharge opening of the unloading conveyor for receiving the flow of grain discharged therefrom. This can be relatively easy to accomplish if the harvester and receiving truck or wagon are stationary, but becomes more difficult if the harvester and the receiving truck or wagon are moving, and the difficulty increases further if the terrain is uneven and/or sloped, and/or a strong, gusting, and/or direction changing wind is present. Further, the grain holding capacity of many harvesters and receivers is quite large, and it may be required to have a capability to vary the grain flow location to spread the grain within a receiving truck or wagon to prevent spillage over the side of the receiver.
Still further, autonomous operation of harvesters and grain receiving vehicles is becoming more common, and it is desirable to have an improved capability to vary grain flow to a receiving vehicle to compensate or adjust for variances in the distance between or travel paths of the harvester and receiving vehicle, as well as elevational and angular differences. In this latter regard, to maintain productivity, it may be desired to unload while moving, with one or both of the harvester and receiving vehicle traversing uneven terrain, and/or tilted sidewardly, which may require frequent adjustments in grain flow location to achieve desired grain distribution within the receiving vehicle. It may also be desirable to enhance or increase the effective length of the unloading conveyor, particularly one with a downwardly facing discharge opening, without materially increasing the physical length of the conveyor, particularly when in its stored or transport position extending rearwardly from the harvester.
An anti-dribble capability is also a desirable feature, as it limits inadvertent grain loss and possible crop emergence in undesired areas where loose grain is dropped. And, an ability to provide a closure for the discharge opening of an unloading conveyor is desirable, to reduce grain dribbling, and to reduce or prevent entry of contaminants such as moisture, dust, leaves and the like, and also birds and rodents.
Accordingly, what is sought is a grain unloading conveyor apparatus and system which provides one or more of the capabilities, and overcomes one or more of the shortcomings and limitations, set forth above.